Canavan Disease by Jeremy Tan Canavan Disease (also known as Canavan-van-Bogaert-Bertrand Disease, Spongy degeneration of the Central Nervous System, Aspartoacylase Deficiency, and ASPA Deficiency) is a brain degenerative disease that belongs to the group of brain degenerative diseases that are characterized by the degeneration of myelin insulation of nerve fibers called leukodystrophies. It is an inherited disease most common among descendants of Jewish people from central or eastern Europe known as Ashkenazi Jews. The gene that is responsible for this disorder is located on Chromosome 17. Genetics Canavan disease is an inherited disorder that is caused by a point mutation of the ASPA gene on the back end of Chromosome 17. The ASPA gene is responsible for the coding of an enzyme called aspartoacylase. The enzyme, aspartoacylase, is vital to the break-down of N-acetyl-aspartic acid (NAA), which plays a role of the production of myelin on nerve fibres, but its purpose is still unknown as of now. The disorder belongs to a group of disorders called leukodystrophies that are characterized by the degeneration of myelin insulation of nerve fibres in the brain. Several records have shown high amounts of N-acetyl-aspartic acid in the brains of patients that are 200 times the amount of a known carrier of the trait that is of the same age as the patient.
How Common is it? Canavan disease is most common with the people of Ashkenazi Jewish descent. It affects about 1 person in 6400 people to 13500 in the Ashkenazi Jewish population. Both parents have to be carriers of this disorder for the child to be affected by this disorder. If both parents are carriers, then there is a 25% chance of having an affected child. http://wiki.ggc.usg.edu/mediawiki/index.php/Canavan
Symptoms
Affected children appear normal until symptoms start showing during the first year of infancy. Infants with Canavan disease tend to be uninterested in things and they are abnormally quiet. The symptoms of this disorder include: · Abnormal posture · Feeding problems (not being able to eat on their own) · Seizures · Joint stiffness · Exaggerated reflexes (hyperflexia) · Loss of tissue in the optic nerve of the eye (optic atrophy) · Mental defect · Blindness · Megalocephaly (abnormally large brain that results in a large head) · Flexion of the arms and legs · Deterioration of motor skills (turning over, head control) · Poor muscle tone · Deafness · Paralysis · Mental retardation
http://wiki.ggc.usg.edu/mediawiki/index.php/Canavan Prognosis The prognosis of this disorder is poor as those affected usually die before the age of 3 but there have been several cases where some have lived to their mid teens or early adulthood. Treatments and Cure There is currently no cure for this disorder as research is still being done and the treatment for this disorder is based on the symptoms. The treatments are to help with the symptoms.
Works Cited "Canavan Disease - Genetics Home Reference." Genetics Home Reference - Your Guide to Understanding Genetic Conditions. Genetics Home Reference, Jan. 2008. Web. 28 Mar. 2011. <http://ghr.nlm.nih.gov/condition/canavan-disease>.
"Canavan Disease Information Page." National Institute of Neurological Disorders and Stroke (NINDS). National Institute of Neurological Disorders and Stroke, 09 Nov. 2010. Web. 24 Mar. 2011. <http://www.ninds.nih.gov/disorders/canavan/canavan.htm>.
David, Zicvc, and David R. Eltzx. "Canavan Disease - PubMed Health." Canavan Disease - PubMed Health. National Center for Biotechnology Information, 11 Oct. 2010. Web. 30 Mar. 2011. <http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002553/>.
Kniffin, Cassandra L., Marla J. F. O'Neill, Ada Hamosh, and Victor A. MacKusick. "Canavan Disease." Canavan Disease - OMIM Result. National Center for Biotechnology Information - Online Mendelian Inheritance in Man, 06 May 2008. Web. 30 Mar. 2011. <http://www.ncbi.nlm.nih.gov/omim/271900>.
by Jeremy Tan
Canavan Disease (also known as Canavan-van-Bogaert-Bertrand Disease, Spongy degeneration of the Central Nervous System, Aspartoacylase Deficiency, and ASPA Deficiency) is a brain degenerative disease that belongs to the group of brain degenerative diseases that are characterized by the degeneration of myelin insulation of nerve fibers called leukodystrophies. It is an inherited disease most common among descendants of Jewish people from central or eastern Europe known as Ashkenazi Jews. The gene that is responsible for this disorder is located on Chromosome 17.
Genetics
Canavan disease is an inherited disorder that is caused by a point mutation of the ASPA gene on the back end of Chromosome 17. The ASPA gene is responsible for the coding of an enzyme called aspartoacylase. The enzyme, aspartoacylase, is vital to the break-down of N-acetyl-aspartic acid (NAA), which plays a role of the production of myelin on nerve fibres, but its purpose is still unknown as of now. The disorder belongs to a group of disorders called leukodystrophies that are characterized by the degeneration of myelin insulation of nerve fibres in the brain. Several records have shown high amounts of N-acetyl-aspartic acid in the brains of patients that are 200 times the amount of a known carrier of the trait that is of the same age as the patient.
http://wiki.ggc.usg.edu/mediawiki/index.php/Canavan
How Common is it?
Canavan disease is most common with the people of Ashkenazi Jewish descent. It affects about 1 person in 6400 people to 13500 in the Ashkenazi Jewish population. Both parents have to be carriers of this disorder for the child to be affected by this disorder. If both parents are carriers, then there is a 25% chance of having an affected child.
http://wiki.ggc.usg.edu/mediawiki/index.php/Canavan
Symptoms
Affected children appear normal until symptoms start showing during the first year of infancy. Infants with Canavan disease tend to be uninterested in things and they are abnormally quiet. The symptoms of this disorder include:· Abnormal posture
· Feeding problems (not being able to eat on their own)
· Seizures
· Joint stiffness
· Exaggerated reflexes (hyperflexia)
· Loss of tissue in the optic nerve of the eye (optic atrophy)
· Mental defect
· Blindness
· Megalocephaly (abnormally large brain that results in a large head)
· Flexion of the arms and legs
· Deterioration of motor skills (turning over, head control)
· Poor muscle tone
· Deafness
· Paralysis
· Mental retardation
http://wiki.ggc.usg.edu/mediawiki/index.php/Canavan
Prognosis
The prognosis of this disorder is poor as those affected usually die before the age of 3 but there have been several cases where some have lived to their mid teens or early adulthood.
Treatments and Cure
There is currently no cure for this disorder as research is still being done and the treatment for this disorder is based on the symptoms. The treatments are to help with the symptoms.
Works Cited
"Canavan Disease - Genetics Home Reference." Genetics Home Reference - Your Guide to
Understanding Genetic Conditions. Genetics Home Reference, Jan. 2008. Web. 28 Mar. 2011.
<http://ghr.nlm.nih.gov/condition/canavan-disease>.
"Canavan Disease Information Page." National Institute of Neurological Disorders and Stroke
(NINDS). National Institute of Neurological Disorders and Stroke, 09 Nov. 2010. Web. 24
Mar. 2011. <http://www.ninds.nih.gov/disorders/canavan/canavan.htm>.
David, Zicvc, and David R. Eltzx. "Canavan Disease - PubMed Health." Canavan Disease - PubMed
Health. National Center for Biotechnology Information, 11 Oct. 2010. Web. 30 Mar. 2011.
<http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002553/>.
Kniffin, Cassandra L., Marla J. F. O'Neill, Ada Hamosh, and Victor A. MacKusick. "Canavan
Disease." Canavan Disease - OMIM Result. National Center for Biotechnology Information -
Online Mendelian Inheritance in Man, 06 May 2008. Web. 30 Mar. 2011.
<http://www.ncbi.nlm.nih.gov/omim/271900>.
All photos on this page came from <http://wiki.ggc.usg.edu/mediawiki/index.php/Canavan>